Rule 10: Minify JavaScript

Rule 11: Avoid Redirects

Not mentioned in the book, but it's better to serve both desktop and mobile versions of a page from the same URL.

Rule 12: Remove Duplicate Scripts

Make sure scripts are included only once.

Rule 13: Configure ETags

Either turn off ETags or generate ETags that uniquely identify a specific version of a resource. The default ETag formats of popular web servers are not cache-friendly.

Rule 14: Make Ajax Cacheable

Make Ajax response cacheable by following rule 3, 4, 9, 10, 11, 13.

High Performance Web Sites is short and easily digestible. It's a pertinent book on speed optimization for web developers, although professional web frontend engineers may find it short of original ideas they are not already aware of.